:root{--bg:#f5fbff;--white:#fff;--tint:#eaf7fc;--cyan:#25c8d1;--sky:#25b6e8;--blue:#1787db;--navy:#174b78;--title:#173b60;--text:#2d4359;--muted:#687f93;--line:#dcebf3;--footer:#123653;--shadow:0 12px 36px rgba(22,75,120,.065)}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.8 Arial,'PingFang SC','Microsoft YaHei',sans-serif}body.drawer-open{overflow:hidden}a{color:inherit;text-decoration:none}a:focus-visible,button:focus-visible{outline:3px solid var(--blue);outline-offset:4px}img{max-width:100%}.wrap{width:min(1160px,calc(100% - 48px));margin-inline:auto}.skip-link{position:absolute;left:12px;top:-60px;background:white;z-index:90;padding:10px}.skip-link:focus{top:10px}.site-header{position:sticky;top:0;z-index:40;background:#fff;border-bottom:1px solid var(--line);box-shadow:0 4px 22px rgba(22,75,120,.035)}.site-header-inner{height:72px;display:flex;align-items:center;gap:22px}.brand{display:inline-flex;align-items:center;gap:9px;flex-shrink:0;min-width:150px}.brand img{display:block;max-width:180px;height:38px;width:auto;object-fit:contain}.brand-symbol{display:grid;place-items:center;font-size:30px;color:var(--cyan);width:40px;height:40px;border-radius:12px;background:var(--tint)}.brand-name{font-size:19px;font-weight:800;color:var(--title);line-height:1.2}.brand-name small{display:block;font-size:9px;letter-spacing:.14em;color:var(--muted)}.desktop-nav{display:flex;align-items:center;gap:5px;justify-content:center;flex:1}.desktop-nav a{font-size:14px;font-weight:650;white-space:nowrap;padding:8px 9px;border-radius:8px;color:var(--navy)}.desktop-nav a:hover,.desktop-nav a.active{background:#eaf9fd;color:#087cb6}.main-btn{display:inline-flex;align-items:center;justify-content:center;min-width:82px;height:42px;padding:0 20px;border-radius:999px;background:linear-gradient(110deg,#25c8d1,#25b6e8,#1787db);color:white;font-weight:700;white-space:nowrap;box-shadow:0 7px 16px rgba(37,182,232,.2);transition:filter .2s,transform .2s}.main-btn:hover{filter:brightness(1.06);transform:translateY(-1px)}.menu-toggle{display:none;border:0;background:transparent;width:42px;height:42px;padding:10px;cursor:pointer}.menu-toggle span{display:block;height:2px;background:var(--title);margin:5px 0;border-radius:2px}.menu-shade{position:fixed;inset:0;background:rgba(15,37,57,.46);visibility:hidden;opacity:0;pointer-events:none;transition:opacity .2s,visibility .2s;z-index:59}.drawer{position:fixed;left:0;top:0;bottom:0;z-index:60;width:min(85vw,360px);background:#fff;transform:translateX(-101%);visibility:hidden;transition:transform .22s,visibility .22s;overflow-y:auto;box-shadow:20px 0 40px rgba(0,0,0,.08)}.drawer-open .menu-shade{visibility:visible;opacity:1;pointer-events:auto}.drawer-open .drawer{transform:translateX(0);visibility:visible}.drawer-head{display:flex;justify-content:space-between;align-items:center;background:var(--tint);padding:19px 22px;font-weight:800;color:var(--title)}.drawer-head button{background:none;border:0;color:var(--title);font-size:31px;cursor:pointer}.drawer nav{padding:12px 24px 36px}.drawer nav p{font-weight:800;font-size:13px;letter-spacing:.07em;color:var(--blue);margin:17px 0 6px}.drawer nav a{display:block;padding:9px 0;border-bottom:1px solid var(--line);font-size:15px}.drawer nav a:hover{color:var(--blue)}.eyebrow{font-size:12px;letter-spacing:.16em;color:#078ba9;font-weight:800;text-transform:uppercase}.hero{padding:48px 0 36px}.hero-grid{display:grid;grid-template-columns:1.04fr .96fr;gap:34px;align-items:center}.hero h1{font-size:40px;line-height:1.35;color:var(--title);margin:14px 0 20px;letter-spacing:-.025em}.hero p{font-size:17px;max-width:580px;color:#49667c}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:26px}.ghost-btn{display:inline-flex;align-items:center;border:1px solid #b8ddea;background:#fff;color:var(--navy);border-radius:999px;padding:7px 20px;font-weight:700}.ghost-btn:hover{background:#effbff}.media{display:flex;justify-content:center;align-items:center;width:100%;overflow:hidden;background:var(--tint);border-radius:16px;aspect-ratio:16/10;border:1px solid var(--line)}.media img{display:block;width:auto;height:auto;max-width:100%;max-height:100%;object-fit:contain;object-position:center}.hero-media{aspect-ratio:16/10}.portrait-media{aspect-ratio:4/5;max-width:350px;margin:auto}.wide-media{aspect-ratio:21/9}.media-fallback{width:100%;height:100%;min-height:130px;background:radial-gradient(circle at 75% 25%,rgba(37,200,209,.2),transparent 38%),linear-gradient(130deg,#e1f6fa,#f2fbff);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:16px;color:#50839b;text-align:center;font-size:13px;padding:18px}.fallback-orbit{width:86px;height:86px;border-radius:50%;border:7px solid rgba(37,182,232,.15);box-shadow:0 0 0 17px rgba(37,200,209,.06);position:relative}.fallback-orbit:after{content:'';position:absolute;inset:19px;border-radius:50%;background:linear-gradient(135deg,var(--cyan),var(--blue));opacity:.38}.section{padding:26px 0 30px}.section-title{display:flex;justify-content:space-between;align-items:end;gap:20px;margin-bottom:22px}.section-title h2,.content-section h2{margin:0 0 10px;font-size:26px;line-height:1.4;color:var(--title)}.section-title p{margin:0;max-width:720px;color:var(--muted)}.section-title a{font-size:14px;font-weight:700;color:var(--blue);white-space:nowrap}.grid-3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.grid-2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.feature-card,.topic-card,.panel,.article-box,.faq-item{background:#fff;border:1px solid var(--line);border-radius:16px;box-shadow:var(--shadow)}.feature-card{padding:24px;transition:transform .2s,border-color .2s}.feature-card:hover{transform:translateY(-3px);border-color:#83cddd}.feature-card .number{color:#10a4bd;font-size:12px;font-weight:800;letter-spacing:.15em}.feature-card h3{font-size:19px;margin:12px 0 9px;color:var(--title);line-height:1.4}.feature-card p{font-size:14px;color:var(--muted);margin:0 0 15px}.feature-card .go{font-size:14px;color:var(--blue);font-weight:700}.topic-card{overflow:hidden}.topic-card .media{border:0;border-radius:0;aspect-ratio:16/9}.topic-card-content{padding:20px}.topic-card h3{font-size:19px;color:var(--title);margin:5px 0 8px}.topic-card p{margin:0 0 12px;color:var(--muted);font-size:14px}.tag{display:inline-block;background:#e4f8fb;color:#068ca4;border-radius:50px;padding:3px 10px;font-size:12px;font-weight:800}.split{display:grid;grid-template-columns:1fr 1fr;gap:32px;align-items:center}.panel{padding:27px}.panel h3{color:var(--title);margin:0 0 9px;font-size:20px}.panel 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.article{max-width:820px;margin-inline:auto}.article{min-width:0}.article p{margin:0 0 18px}.article h2{font-size:25px;color:var(--title);line-height:1.45;margin:36px 0 15px}.article h3{font-size:19px;color:var(--title);line-height:1.45;margin:24px 0 10px}.article ul,.article ol{padding-left:23px;margin:12px 0 20px}.article li{margin-bottom:9px}.article .media{margin:20px 0 27px}.article .lead{font-size:18px;color:#395b75;line-height:1.85}.side-panel{position:sticky;top:105px;border:1px solid var(--line);border-radius:14px;padding:22px;background:#fff}.side-panel h2{font-size:18px;color:var(--title);margin:0 0 12px}.side-panel a{display:block;padding:10px 0;border-bottom:1px solid var(--line);font-size:14px;color:var(--navy)}.side-panel a:hover{color:var(--blue)}.side-panel a:last-child{border:0}.info-strip{border-left:4px solid var(--cyan);padding:14px 20px;background:#e7f9fc;border-radius:0 12px 12px 0;margin:24px 0;color:#245577}.compare-table{width:100%;border-collapse:collapse;margin:20px 0 28px;font-size:15px;background:#fff}.compare-table th,.compare-table td{border:1px solid var(--line);padding:13px 15px;vertical-align:top;text-align:left}.compare-table th{background:#e4f7fb;color:var(--title)}.article-box{padding:24px;margin:25px 0}.article-box h3{margin-top:0}.two-notes{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin:24px 0}.note{background:#fff;padding:23px;border:1px solid var(--line);border-radius:14px}.note h3{margin-top:0}.related{padding:23px 0;margin-top:36px;border-top:1px solid var(--line)}.related h2{font-size:23px;color:var(--title)}.related-links{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:13px}.related-links a{display:flex;justify-content:space-between;gap:8px;padding:14px;background:white;border:1px solid var(--line);border-radius:11px;color:var(--navy);font-size:14px;font-weight:700}.related-links a 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@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition:none!important}}